What You Really Need To Know About Sharks And Their Behavior, According To South Florida Experts And Conservationists

What You Really Need To Know About Sharks And Their Behavior, According To South Florida Experts And Conservationists

by Lyssa Goldberg Oct 2016 Also on Digital Edition

See the word “shark” in a headline or hear it in a television newscast, and it’s sure to grab attention. Few creatures on this planet are as feared yet revered. To help us understand these enigmatic creatures, we spoke with six local shark experts and conservationists, who are working to demystify the behaviors of the ocean’s most popular predators.

Unprovoked shark attacks reached an all-time high last year (98), with Florida leading the U.S. in the number of reported incidents (30)—but “attack” is an inaccurate word, according to Jupiter-based underwater photographer Craig Dietrich. “Sharks don’t go looking for people. They are swimming in their environment, and humans have put themselves in the shark’s environment,” he says. “In general, sharks do not eat humans after a bite—they realize what they’ve bitten is not a food source.” 

This increase is indicative of a change in, not sharks, but humans. Given population growth, there are more people going to the beach and swimming in the ocean.

The number of people being bitten by sharks is simply rising proportionally, suggest local researchers like Stephen Kajiura, biological sciences professor at Florida Atlantic University. “If you look at the number of people who move to Florida each day, it’s dramatic, and those people are coming here for the beaches,” he says. 

Fortunately, all of the experts we spoke with agreed: Positive public sentiment toward sharks is on the rise, too. Yes, people have started realizing real life doesn’t look like “Jaws,” and Discovery Channel’s Shark Week programming has moved from sensational to scientific—but there’s still more work to be done. 

Michael Dornellas

Diving guide and videographer, Reefhunter

Photo by Jason Nuttle

Google search Michael Dornellas, and viral videos with titles like “Diver ‘Hypnotizes’ A 10-Foot Shark” or “Blind Lemon Shark Headbutts A Diver’s Face” surface. The West Palm Beach videographer says he dives with about $10,000 worth of equipment. One time, a tiger shark bit the dome port on his camera (the piece that allows him to take wide-angle shots)—it was about $500 to replace. “I drove around in this piece of crap car [a 1998 Honda Prelude] for the longest time…” he says. “All of my money went to travel and camera gear.” Dornellas began diving with sharks less than three years ago, but the animal first piqued his interest when he was 8 years old. He was spearfishing with his dad in the Abaco Islands of the Bahamas, and a reef shark swam by. “Everyone was scared and so was I, but my fascination was stronger than my fear,” he says. “I wanted to watch it swim and remember just how amazing I thought it was.” When Dornellas isn’t diving, he’s likely chasing alligators, crocodiles or snakes, or compiling footage on his site, vimeo.com/reefhunter, with clips having been picked up by Discovery Channel during Shark Week.

What’s your wildest shark story? 

I was coming up from a dive, and a big lemon that was blind in one eye collided into my face, knocking my mask off. It hurt. 

What do you want Floridians to know about sharks? 

I want people to know that sharks are not out to eat people. We can coexist with these animals in an amazing way. I want people to see them as I do, as an amazing predator in need of protection, just like wolves and other creatures we already protect. If sharks were out there to eat humans, they would be following tourist migrations and not fish migrations. 

What’s your favorite shark species and why? 

It’s a tie between bull sharks and tigers. Tiger sharks are large and very unique in the way they interact. They are beautiful and have unreal killing power, yet they can be the most gentle and curious creatures. Bull sharks are fast and unpredictable. They are pack hunters and move with this ominous posture. From twitching pectoral fins to the quick turns, they are very intimidating. They are also the deadliest species of sharks, yet I have found ways to interact very closely and have found that they too can be very calm and social­—coming up very slow, allowing me to place my hands gently on their noses. 

What’s the most interesting trivia knowledge you can offer about sharks? 

The gel in the shark’s sensory organs is the most conductive material know to man. In theory, they can [sense] the blood moving through your veins. 

If you encounter a shark while you’re in the ocean, what should you do? 

Keep calm and maintain eye contact. [Some shark species] are ambush predators and will usually always approach from blind spots.


Dr. Mahmood Shivji

Professor at Nova Southeastern University, and director of the Guy Harvey Research Institute and Save Our Seas Shark Research Center

Photo by Jason Nuttle

A first encounter with a shark could be considered intimidating. However, for Dr. Mahmood Shivji, that first interaction didn’t involve just one, but about 600 spiny dogfish sharks 3 to 3.5 feet in length during a scuba diving trip to explore a ship wreck on the west coast of Vancouver Island, Canada. “As we descended through this [grouping of sharks], the sharks would only slightly part, and many would bump into us before turning away. ... It was quite a surreal visual experience,” says the Nova Southeastern University professor who’s been researching the animals for more than 20 years. As the director of the Guy Harvey Research Institute and Save Our Seas Shark Research Center, Shivji’s recent work has explored how the genomes of sharks can be applied to creating drugs that fight human cancers. “Sharks are well known for their ability to heal from even large and deep wounds exceptionally quickly,” he says. “... There are tantalizing prospects that studying sharks will reveal discoveries that could benefit human medicine in the future.” 

What is it about sharks that fascinates you?

Sharks are one of the oldest surviving vertebrate groups, with fossil evidence for their existence dating back to at least 420 million years ago. This is much older than even dinosaurs, whose first appearance in the fossil record dates back to about 240 million years ago. For contrast, our species (Homo sapiens) dates back to only about 200,000 years ago.

Shivji surgically implants an acoustic transmitter into an adult tiger shark to determine how the species moves around deep coral reefs in the Caribbean. (Photo by Bradley Wetherbee, Guy Harvey Research Institute)
What do you want Floridians to know about sharks?

These animals deserve our admiration and respect as evolutionary marvels whose features have been honed over millions of years of evolution. Equally importantly, as upper-food-web creatures, sharks are key components of our oceans and [are] needed to keep our marine ecosystems functioning properly. As such, it’s important to make sure that we conserve sharks (and, indeed all marine wildlife) and their habitats.

What’s your favorite shark species and why?

Probably the shortfin mako (a close cousin of the white shark). We do a lot of research on this species. It’s shaped like a torpedo, thought to be the fastest swimming of sharks, is partially warm-bodied (unlike most sharks), and migrates enormous distances but also comes back to the same places after wandering off for thousands of miles. ... Unfortunately, makos are also overfished in some parts of the world.

Follow the movements of makos and other sharks the Guy Harvey Research Institute tracks using satellite tags on ghritracking.org.


Bryce Rohrer

Captain and diver, Florida Shark Diving

Photo by Jason Nuttle

Bryce Rohrer started taking out divers to see sharks off of Nantucket in 2010. Running a shark diving company out of New England, however, proved to be limiting for business. Come fall, the freediver would find himself sitting on his couch, watching football as the weather grew cold, thinking, “I’ve got to go somewhere [where I can swim] year round.” Sunny South Florida was his answer. “I came here to Jupiter/Palm Beach because this area is basically one of the most shark-prone areas in the entire East Coast,” says the Connecticut native. In 2012, Rohrer founded Florida Shark Diving in Jupiter, taking adventurous clients out on his charter boat. He facilitates encounters for everyone from professional photographers to families with young kids looking for a once-in-a-lifetime experience. The stakes are high, Rohrer notes, so he ensures every detail is arranged for a safe and enjoyable day. “Ten years ago, everyone wanted to come out and fish for sharks and kill them; now, instead they want to go dive and see sharks, or go get selfies with sharks,” he says. 

What is it about sharks that fascinates you?

To me, it’s the power of wildlife more than anything. To me, nature is one the purest parts of our lives, so to be able to spend time with and work alongside the top representatives of that world is an amazing way to live.

What’s your favorite shark species and why?

Mako. They are nothing but pure speed, power and aggression almost 24/7. The perfect apex predator (animal at the top of the food chain).

Bryce Rohrer encounters a tiger shark on a dive in the Bahamas last spring (Photo by Craig Dietrich)
What do you want Floridians to know about sharks?

They are a major [keystone species] and vital to the health of the oceans, and without them, it would cause major environmental issues. They’re not here to hurt you; they need to be protected and valued.

What’s a common misconception about them?

The misconception is they’re blood-thirsty killers. The reality is they’re extremely cautious and calculating animals. You don’t get to be one of the oldest living species on the planet by being dumb. They are easily one of the most misunderstood subjects of all time.


Randy Jordan

Shark Advocate And Captain Of Emerald Charters

Photo by Jason Nuttle

Looking to find Randy Jordan out on the water? Just search for his sharp-toothed, seafoam green boat in Jupiter. Captain of Emerald Charters, Jordan makes his living by guiding experienced divers who have “diving with sharks” as a bullet point on their bucket lists. He puts one twist on the typical shark encounter, though: he feeds the animals. This sends the message that sharks are looking for food, but humans are not on their menu, Jordan suggests. “When they get to see a shark interaction during a feeding, they’re usually pretty surprised that I’m able to put food out and have the shark eat it out of my hand—but not have it eat my hand,” he says. However, critics argue these feedings can change sharks’ behaviors. In 2014, Jordan created a stir when he was charged with illegal shark feeding, which is prohibited in Florida state waters within 3 miles from shore. Jordan says he helped support the regulation when it first got passed, but after an investigation found his boat “within a football field inside” the 3-mile mark, he was fined $200 by the Florida Fish and Wildlife Conservation Commission and put on one year’s probation. Jordan has since continued leading shark feedings farther out from shore. While he acknowledges “there’s no training manual for feeding sharks,” seeing one swim up close remains a majestic experience for his guests. “It’s like going on a safari and seeing a lion,” he says.

Tell me your first shark memory.

Being an avid spear fisherman, I’ve spearfished in Jupiter and all over, but when I spearfished in Jupiter, I’d look down there, and there would be two to three kinds of sharks. The first time I saw a hammerhead shark, I honestly hyperventilated. I thought the hammerhead was going to get me. I gave up my dinner … and got out of the water.

Pictured above is the Emerald Charters signature boat on which Randy Jordan takes his diving clients. (Photo by Craig Dietrich)
What’s your favorite shark species and why?

Tigers. They’re very polite. 

What’s an interesting piece of trivia knowledge you can offer about sharks?

Most live to about 50 but don’t breed until 20. They have a two-year gestation period and only produce about 12 pups. That’s not a sustainable fishery. [Editor’s note: Actual numbers vary by shark species; while some sharks might breed earlier in life, they may correspondingly have shorter lifespans, which limits population growth. For example, female blacktip sharks mature at around 7 years old and live for about 12 to 15 years.]


Craig Dietrich

Underwater photographer

Photo by Jason Nuttle

Babies and sharks are in most ways pretty different creatures. But for Craig Dietrich, an underwater photographer who has made swimming with sharks a career, his skills were first honed at a baby portrait studio in North Carolina. Dietrich followed an advertisement to a diving photographer job in Monterey, California. Through the position, he gained access to equipment he otherwise couldn’t afford or learn to use. And when his family moved to South Florida, he kept at it—half of the time diving in Jupiter. To make a return on his hobby, Dietrich began selling his photos at art shows and in local galleries. “It’s been four years since I’ve been self-employed as an underwater photographer,” he says. “The chance of making it at this job is very, very slim.” Dietrich’s artwork can be found in galleries from South Florida to California, and he is a regular at art festivals in Broward and Palm Beach counties. This year, he won first place at the annual Delray Affair in downtown Delray Beach.

Tell me your first shark memory.

Being on a shark dive in the Bahamas. I was fascinated by how big the reef sharks were. Then, the lemon sharks showed up, and I was shocked at how big they were. ... Until the tiger sharks came. It was like going from a Volkswagen to an SUV to an 18-wheeler.

What’s your favorite shark species and why?

I am partial to the tiger shark. They are visually a beautiful shark due to their stripes and spots. They also are a visually powerful shark. Both their strength and intelligence are apparent just by looking at them, but they are extremely graceful at the same time. 

Examples of Dietrich’s work that is sold at local art festivals
What do you want Floridians to know about sharks?

Two things: 1) Sharks do not eat people. 2) “Jaws” was only a movie.

If you encounter a shark while you’re in the ocean, what should you do?

Enjoy the sighting! It’s unlikely the shark will approach you.


Stephen Kajiura

Biological sciences professor, Florida Atlantic University

Photo by Jason Nuttle

Shark researcher Stephen Kajiura was 21 when he first saw the ocean, though he’d been enthralled by sharks since age 4. “Little kids love animals. Anything that was in the ocean was cool, and sharks in particular were, ugh, so cool,” he says. The Canadian grew up far away from them, however, and learned about sharks through the Jacques Cousteau specials he’d watch. “When you go diving in a lake up in Ontario, you see one fish—that’s exciting,” he says. Kajiura first came upon the Atlantic Ocean during a field excursion in college, and then in pursuit of his master’s degree, he made his first appearance in Florida. Kajiura later returned to South Florida’s warm waters for a full-time faculty position at FAU in Boca Raton, where, during the last six years, he has carved a niche for himself researching blacktip sharks’ migration patterns. “What happened was I would get inquiries from local TV stations every winter: ‘Our helicopters are seeing all these sharks right off the coast—should I be concerned?’” There wasn’t much literature on the subject, so Kajiura decided to look into it himself. Now every winter during the sharks’ migration season, Kajiura takes out his own helicopter on a weekly basis to count the number of sharks visiting South Florida waters and monitors them with tracking devices. In fact, footage he took of tens of thousands of sharks swimming close to shore went viral earlier this year.

What’s something most people don’t realize about your job?

I spend most of my time sitting in front of the computer, not out on the water.

What’s your favorite shark species and why?

Hammerhead. Their bizarre head shape is fascinating from an evolutionary perspective.

What do you want Floridians to know about sharks?

You have a much better chance of being killed while driving to the beach than you do of being killed by a shark once you get there.  

What’s your wildest shark story?

While fishing for juvenile sharks in the Keys, most students were using a rod and reel, but we were short on fishing rods, so someone put a fish head in a dip net and held the net over the back of the boat. I assured her that no shark would swim into the small dip net. Suddenly, the peaceful quiet was shattered by a tremendous splashing and commotion, and everyone was shocked that a small nurse shark swam right into the dip net. Her ‘dip-net-with-a-fish-head’ technique caught a shark before anyone else.

Tens of thousands of blacktip sharks are seen swimming off the coast of Palm Beach this past winter. (Photo by Stephen Kajiura)


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FAU Shark Researcher Worked With Discovery Channel On A Documentary Airing During Shark Week

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